U.S. Army Sgt. Dan Glenn inspects the auxiliary power unit fuel shut-off switch on a CH-47 Chinook helicopter during start-up procedures before a personnel and equipment movement mission on Bagram Airfield, Afghanistan, Sept. 22, 2013. Glenn, a crew chief, is assigned to the Texas-Oklahoma National Guard's Company B, 2nd Battalion General Support, 149th Aviation Regiment, which is attached to the 10th Combat Aviation Brigade. U.S. Army Sgt. Dan Glenn inspects the auxiliary power unit fuel shut-off switch on a CH-47 Chinook helicopter during start-up procedures before a personnel and equipment movement mission on Bagram Airfield, Afghanistan, Sept. 22, 2013. Glenn, a crew chief, is assigned to the Texas-Oklahoma National Guard's Company B, 2nd Battalion General Support, 149th Aviation Regiment, which is attached to the 10th Combat Aviation Brigade. SHARE: Download: Full Size (2.39 MB) Tags: Photo Essays Credit: VIRIN: 594503-K-TFJ53-901.jpg Photo Gallery